diff --git a/store/index.js b/store/index.js
index 1963310..7332184 100644
--- a/store/index.js
+++ b/store/index.js
@@ -433,10 +433,14 @@ function unifyCommitArgs(type, payload = {}, options = {}) {
 }
 
 function collectState(store) {
-  let state = store.state || {}
+  let state =
+    store.state && typeof store.state === 'function'
+      ? store.state()
+      : store.state || {}
   function collectModuleState(module, moduleName, moduleState) {
     if (moduleName) {
-      moduleState[moduleName] = module.state
+      moduleState[moduleName] =
+        typeof module.state === 'function' ? module.state() : module.state
     }
     if (module.modules) {
       forEachValue(module.modules, (childModule, childModuleName) => {
diff --git a/store/index.test.ts b/store/index.test.ts
index b3298f9..beeb941 100644
--- a/store/index.test.ts
+++ b/store/index.test.ts
@@ -869,7 +869,7 @@ it('applies old actions from store in modules', async () => {
     {
       user: {
         namespaced: false,
-        state: { value: 0 },
+        state: () => ({ value: 0 }),
         mutations: {
           'user/historyLine': historyLine
         }
@@ -1033,7 +1033,7 @@ it('applies old actions from store in nested modules', async () => {
   }
 
   let store2 = _createStore2<Store2State>({
-    state: { value: 0 },
+    state: () => ({ value: 0 }),
     mutations: { historyLine },
     modules: {
       a: {
@@ -1047,7 +1047,7 @@ it('applies old actions from store in nested modules', async () => {
             modules: {
               c: {
                 namespaced: true,
-                state: { value: 0 },
+                state: () => ({ value: 0 }),
                 mutations: { historyLine },
                 modules: {
                   d: {